Press Release

Amunix Announces Update To Licensing Agreement With Janssen For Its Proprietary Xten Technology

Mountain View, CA – August 14, 2013 – Amunix Operating Inc. (Amunix), today announced that an option for an additional product has been exercised under its worldwide research collaboration and licensing agreement with Janssen Biotech, Inc. (Janssen).  Under the exercised option, Amunix will combine its XTEN half-life extension technology with a lead therapeutic molecule selected by Janssen, which will be responsible for all preclinical and clinical development as well as the commercialization of the product.  Amunix will receive an option payment in addition to research funding and will be eligible for future milestone and royalty payments.  Additional financial terms will not be disclosed.

“We are very pleased with the progress of our collaboration with Janssen,” said Volker Schellenberger, PhD, Amunix President and CEO.  “Amunix continues to advance its XTEN half-life extension platform and remains focused on its application in advancing therapeutics.”

About Amunix

Amunix Operating Inc., based in Mountain View, CA, is a privately held biotechnology company focused on the discovery and development of novel therapeutics with improved in vivo half-lives. Amunix’s half-life extension technology is based on XTEN; hydrophilic, unstructured, biodegradable polypeptides that impart a number of favorable properties upon the molecules to which it is attached. XTEN can be recombinantly fused or chemically conjugated to peptides, proteins, and other pharmaceuticals. Besides the advantages of a lower dosing frequency, XTENylation also stabilizes plasma drug concentrations, which often results in increased efficacy as well as reduced side effects.  Two genetically fused XTENylated products, VRS-859 (Exenatide-XTEN) and VRS-317 (human Growth Hormone-XTEN) have completed Phase 1a studies through Amunix partners Diartis and Versartis, respectively.  VRS-317 is currently undergoing a Phase 1b/2a trial in pediatric growth hormone deficient patients.  Amunix is also working with Biogen-Idec in the hemophilia space as well as several other undisclosed partners in various other therapeutic areas.   Amunix is actively seeking partnerships for application of its XTEN technology. For additional information about the company please visit